Unit test improvements to fully validate the SkImage contract

src/image/SkImage_Picture.cpp

 /*
  * Copyright 2012 Google Inc.
  *
  * Use of this source code is governed by a BSD-style license that can be
  * found in the LICENSE file.
  */
 
 #include "SkImage_Base.h"
 #include "SkImagePriv.h"
 #include "SkPicture.h"
 
 class SkImage_Picture : public SkImage_Base {
 public:
     SkImage_Picture(SkPicture*);
     virtual ~SkImage_Picture();
 
     virtual void onDraw(SkCanvas*, SkScalar, SkScalar, const SkPaint*) SK_OVERRIDE;
 
+    SkPicture* getPicture() { return fPicture; }
+
 private:
     SkPicture*  fPicture;
 
     typedef SkImage_Base INHERITED;
 };
 
 ///////////////////////////////////////////////////////////////////////////////
 
 SkImage_Picture::SkImage_Picture(SkPicture* pict) : INHERITED(pict->width(), pict->height()) {
     pict->endRecording();
@@ skipping 16 matching lines @@
      *  its ability to continue recording (if needed).
      *
      *  Optimally this will shared as much data/buffers as it can with
      *  srcPicture, and srcPicture will perform a copy-on-write as needed if it
      *  needs to mutate them later on.
      */
     SkAutoTUnref<SkPicture> playback(SkNEW_ARGS(SkPicture, (*srcPicture)));
 
     return SkNEW_ARGS(SkImage_Picture, (playback));
 }
+
+SkPicture* SkPictureImageGetPicture(SkImage* pictureImage) {
+    return static_cast<SkImage_Picture*>(pictureImage)->getPicture();
+}